1. Field of the Invention
The present invention concerns an apparatus serving to heat a first liquid suspension by means of a second liquid suspension without incurring intermixing of the solids in the two suspension flows, said apparatus consisting of a plurality of series connected units, each of which comprises a pressure chamber, a container closed at its bottom and open at the top disposed within the pressure chamber and provided at the top with a supply conduit for said second heat-releasing liquid suspension and at the bottom with a drain conduit for cooled second liquid suspension, the free space between the wall of the pressure chamber and the inner container being provided at the top with at least two nozzles for the introduction of a jet of said first heat-receiving liquid suspension and at the bottom with a draining pipe line for heated first liquid suspension, and the draining pipe line for the cooled heat-releasing liquid suspension being connected by means of a connecting pipe to the supply pipe line of a preceding unit, and the draining pipe line for heated heat-receiving liquid suspension connected by means of a connecting pipe with incorporated pump, with the nozzles of a subsequent unit.
2. Description of the Prior Art
The invention specifically concerns an arrangement functioning under such pressure and temperature conditions that boiling can take place in said second heat releasing liquid, which shall henceforth be referred to as liquid A, and that condensation of vapor can take place in said heat-receiving liquid, which shall henceforth be referred to as liquid B.
Thus, the object of the invention is to provide an apparatus the operation of which is based on the fact, well-known in itself, that if a liquid is introduced into a space where a temperature prevails which is lower than the vapor pressure consistent with the liquid's temperature, expansion vapor will depart from the liquid which is at the same time cooled to a temperature corresponding to the vapor pressure. The heating in the apparatus is based on the, likewise well-known, phenomenon that if vapor and liquid are mixed in a space where the vapor pressure is higher than the vapor pressure consistent with the temperature of the liquid, vapor will condense onto the surface of the liquid, while the liquid is heated. Since the solid and liquid phases can be effeciently separated from the vapor phase by well-known methods, the vapor departing from liquid A and condensing on liquid B will not transport any solid matter from liquid A to liquid B.
Exchange of heat between two liquids, whereat one of these is heated and the other is cooled, is usually effected in heat exchangers wherein both liquids are caused to flow past a heat-transmission partition separating them. As a result of temperature differences, a heat flow is transmitted through the partition, which also prevents the mixing of the liquids. In applications involving heat exchange between different suspensions such heat exchanges are often altogether inappropriate owing to the fact that the flow passages in the pieces of equipment are blocked by solid material in suspension and that the heat transmission wall soon acquires a coating impeding the flow of heat. In the invention presented here, these problems are avoided.
In a report of the year 1960 by A. B. Svensk Torvforadling, a condenser with built-in cyclone is disclosed. The apparatus consists of a cylindrical pressure vessel standing in vertical position and having a nozzle at the top for injection of the heat-receiving suspension, and an intermiediate bottom with drain for heated suspension. Piercing the intermiediate bottom, a vertical cylinder is centrally disposed, with an upper tangential input for the heat releasing suspension and with a drain for the cooled suspension on the bottom of the pressure vessel. In order to prevent the downwardly falling drops of heat receiving suspension from becoming mixed with the heat releasing suspension, the vertical cylinder is provided at the top with a screen protecting its mouth aperture from the falling drops and directing the vapors which rise out of the cylinder, to one side so that they are met sidewise by the falling drops.